1. Field of the Invention
The present invention relates to an electrical projectile detonator, in particular a base detonator, which includes a piezoceramic cell forming a current generator in which a voltage can be generated through the gas pressure of a pyrotechnic charge.
2. Discussion of the Prior Art
In electrical projectile detonators which include a piezoceramic cell as a current generator, the cell is mostly so arranged that, either at firing under the effect of inertial forces, or at impact against a target it is exposed to a pressure load or impact load and, as a result, electrical energy is generated therein which is necessary for the detonation of the explosive charge. For this purpose, the cell is arranged either in the tip of the projectile or in the base thereof.
In addition to the foregoing, it has also become known from German Laid-Open Patent application Ser. No. 22 06 646 that the mechanical pressure energy which is required for the generation of the electrical energy can be generated through the intermediary of a pyrotechnic charge.
While the forces which occur during the firing acceleration are sufficient to generate the voltage required for detonation in a piezoceramic cell, this energy is frequently inadequate to concurrently supply occasionally additional electrical circuits which may be present in the detonator. On the other hand, a current source as disclosed in the above-mentioned German patent application requires its own pyrotechnic charge, as well as an auxiliary detonator arrangement.
Consequently, it has already been previously proposed in German Patent application No. P 27 46 599.2 to load or charge a piezoceramic cell in an electrical projectile detonator through the gas pressure of the projectile propellent charge. In accordance with this proposal, the piezoceramic cell is arranged within a recess on the outside of the projectile tail and is covered by a pressure plate which is pressed against the piezoceramic cell by the gas pressure of the projectile propellent charge.
Through this arrangement there is obtained a piezo-ceramic current generator whose output lies considerably above those of the piezoceramic current generators which operate under inertial force. The thus generated electrical energy is conducted through gas-tight conduit passageways towards the electronic power storage circuitry which is positioned interiorly of the projectile. Hereby, the passageways which extend through the projectile base set relatively high constructional demands on the projectile since they must be able to withstand the propellent charge pressure and dependably prevent penetration of the propellent charge gases into the interior of the projectile. This, however, is decisive for the unarmed condition of the detonator of the projectile which equipped with an electrical projectile detonator of that type.